Fish oil is known to be an important source of highly unsaturated n-3 polyunsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which play an important role in the prevention of different human diseases. Fortification of foods with such fatty acids is, thus, increasingly recommended. A growing public awareness about the benefits and the limited dietary sources of PUFA has created a substantial interest in the production of PUFA concentrate. Thus, ecofriendly extraction and purification techniques, exhibiting higher yield and minimum degradation of the nutrient, are of prime focus among the researchers. Due to the presence of these highly unsaturated PUFA, fish oil is highly prone to oxidation, leading to the production of off-odors and off-flavors. Presently, synthetic antioxidants have been replaced by natural ones for stabilizing the fish oil against oxidation. This article reviews major research and patents that have been published on fish oil extraction, purification and its stability.